Transport emissions of air pollutants (CO, NH3, NOx, NMVOC, PM10, SOx) by mode

Generic metadata

Classification

Identification

Acidifying substances

Emission of acidifying substances from transport decreased by 32.4% between 1990 and 2004 in the EEA32. The introduction of both catalytic converters and reduced sulphur in fuels have contributed substantially to this reduction, offsetting the pressure from increased road traffic in the same period. Decreases between 1990 and 2004 in the different country groupings were: 36% in EU25, 36% in EU15, 34% in EU10, 9% in AC4 and 35% in EFTA4. The proportion of emissions emitted from the different country groupings in 2004 was: 73% in EU15, 11% in EU10, 13% in AC4 and 3% in EFTA4.

In the transport sector, NOx is the most important pollutant contributing to the formation of acidifying substances, comprising 88% of total transport-related acidifying emissions in the EEA32. Road transport contributed 14% to the total emissions (i.e. from all sectors) of acidifying substances in 2004 for the EEA32 (15% of total emissions in EU25, 17% EU15, 10% EU10, 10% AC4 and 16% EFTA4).

Further reductions of emissions of acidifying pollutants are needed to reach the 2010 targets of the National Emission Ceilings Directive (Targets: -56.9% for EU25, -56.3% for EU15 and -50.6% for EU10).

Ozone precursors

Emissions of ozone precursors from transport decreased by 41% between 1990 and 2004 in the EEA32. Reductions have occurred mainly because of increased penetration catalytic converters for road vehicles as a result of tightening of EU regulations on new vehicle emissions limits. Decreases were slightly larger in the EU15 (48%), less in the EU10 (31%), AC4 (26%) and larger in the EFTA4 (47%). The proportion of emissions emitted from the different country groupings in 2004 was: 35% in EU15, 39% in EU10, 32% in AC4 and 26% in EFTA4.

Emissions of NOx (61%) and of NMVOC (24%) were the most significant pollutants contributing to the formation of tropospheric ozone in 2004 in the EEA32. Road transport is the dominant source of ozone precursors and contributed 34% of total ozone precursor emissions in 2004 in the EEA32 (35% EU15, 30% EU10, 33% AC4 and 25% EFTA4).

Total ozone precursor emissions are declining in most countries and in the EEA32 as a whole. They decreased by 36% in the EEA32 between 1990 and 2004. Road transport has contributed most strongly to this reduction, as its emissions of ozone precursors decreased by 49% over the same period, with emissions from other transport increasing by 1.5%. The contribution of transport as a whole (road and other) to the total dropped from 50% in 1990 to 46% in 2004.

International transport is a further significant source of ozone precursors such as NOX (see Box 3 - Emissions of acidifying substances from international ship traffic). However, this is not included in the EMEP totals reported above.

Emission reductions so far have not led to fewer exceedances of critical levels (ecosystems) or concentration thresholds (human health). Substantial further reductions of emissions of ozone precursor pollutants from all sectors are required to achieve the Gothenburg Protocol and the National Emission Ceilings Directive 2010 targets. Meeting these targets requires a reduction of about 54.9% of emissions of ozone precursors from 1990 levels by 2010 for the EU25 (-52.9% for EU15 and -26.2% for EU10).

According to recent studies by BMT and Entec UK for the European Commission (European Commission, 2000b and European Commission, 2003), SO2 and NOX from shipping are expected to increase by 2010. This means an associated increase in ozone precursor emissions.

Particulates

Emissions of particulate matter from the transport sector decreased by 29% between 1990 and 2004 in the EEA32 (and 32% in EU25). EEA32 emissions of total primary PM10 and secondary PM10 precursors were reduced by 44% over the same period. The reduction from transport has been achieved largely as a result of the continued penetration of catalytic converters and other improvements to vehicle technology, reducing the emissions of secondary particulate precursors. Decreases were similar in the EU15, EU10 and EFTA4 (33%, 25% and 34% respectively), but smaller in AC4 (10%). The proportion of emissions emitted from the different country groupings in 2004 was: 73% in EU15, 11% in EU10, 12% in AC4 and 3% in EFTA4. There is much better data available on primary particulate emissions for EU10 and AC4 compared to previous years.

Emission of NOX (87%) was the most significant pollutant contributing to atmospheric PM10 in 2004. Road transport is the dominant source of emissions of fine particulates, contributing 22% to the EEA32 total emission of fine particulates.

However, emissions from road transport decreased by 36% between 1990 and 2004, contributing significantly to the overall reduction of particulate emissions. Emissions from sources other than road transport decreased by only 8% over the same period.

Emissions of primary PM10 and secondary PM10 precursors are expected to decrease significantly between 2004 and 2010, as improved vehicle engine technologies are adopted and stationary fuel combustion emissions are controlled through abatement or use of low sulphur fuels such as natural gas. Despite this, it is expected that in the near future in the majority of the urban areas over EU15 territory, PM10 concentrations will still be well above the limit values. Substantial further reductions in all sectors are needed to reach the limit values set in the EU first Daughter Directive to the Framework Directive on Ambient Air Quality. Additional measures to reduce the sulphur content of diesel and petrol fuels have been decided upon by the European Commission (European Commission, 2003), which included the availability of the sulphur-free (<10 ppm sulphur or 'zero sulphur') fuel from 2005 in Member States, and complete transition to sulphur-free fuel by 2009. These measures should reduce emissions of NOX and SOX, as well as primary PM10, from road vehicles in the future.

As mentioned under "ozone precursors", emissions of SO2 and NOX from shipping in European waters are expected to increase by 2010 with an associated increase in primary and secondary PM10 precursors (European Commission, 2000b).